Method of sinking, cleaning, and removing well screens



April 1 1924o 1,488,662

w. H. CATER METHOD OF SINKING, CLEANING, AND REMOVING WELL SCREENS Filed March 17, 1923 .15

F'atented Apr, 1, 11924.

Parana Fries,

WILLIAM H. CATER, F GHICAGO, ILLINOIS.

METHOD 0E SINKING, CLEANING,'AND REMOVING WELL SCREENS.

Application filed March 17, 1923. Serial No. 625,733.

I To all whom it may concern:

Be it known that l, WILLIAM H. CATER, a citizen of the United States, and resident of Chica o, in the county of Cook and State of lllinois, have invented certain new and useful lmprovements'in Methods of Sinking, Cleaning, and Removing W ell Screens, of which the following is a specification. Y I

In the sinking or driving of perforated I or apertured well screens or casings, in their ordinary use and in their withdrawal from the earth, "trouble is frequently encountered by reason of the clogging of the holes of suchscreens or casings by gravel,

sand, dirt and the like, which becomes more or less embedded therein, thus hindering or rendering inefficient the manipulation of the casing or the use of the well.

Accordingly, one object of the present invention is the provision of a simple and effective method of freeing or clearing or cleaning out such holes or apertures whereby the well may function more correctly as and actively, or whereby the casing may be more readily sunk or withdrawn as the case may be.

One operation by which the above-stated object of the invention may be fulfilled consists in subjecting the water which partia lly or wholly fills the casing to a very sudden and high pressure wh1ch forces it out through the casing holes, thus temporarily washing or flushing outwardl fering or clogging dirt or eart such pressure at the same time-loosening or partially removing the earth just beneath the foot of the casing. This pressure is desirably imparted to the water, well known to be substantially non-compressible, by drop in a weight on such bod of water co n within the casin an this is easily and readily accomplis ed' by usingthe excavating pump itself and its load as the. weight for performing the pressure-enforcing operation.

Another operation, by which the abovestated object of the invention mayl be .fulfilled, consists in moving the weig t quick- 1y upward through the well screen, which causes the fine material lying adjacent to the outer side of the screen and more-or (ill the interless clogging the openings thereof to flow into the well, allowing the coarser material to lie adjacent to the screen, and thereby causing a large area of filtration and percolation outside the screen.

While each of these operations is efi'ective to clean, and thus rejuvenate, to a considerable extent, a dirty and clogged screen without the necessity of withdrawing it from the well, yet the screen is most efliciently cleaned, and the best rejuvenating results secured, by performing both of theseand ultimate y discharged from the well.

i A further object of the invention, which is attained by the operations above described, is the development of an underflowage of gravel format-ions'existing in a vein. By subjecting the liquid to sudden pressure, then passing the pump or other weight through the vein, and then raising the pump or weight swiftl the fine material is caused, to enter t' e well and be pumped out when cleaning. By repeating this method it is possible to draw all the fine material from that vein into the well, allowing the coarser material to lie adjacent to the well screen, which builds up a large area lying around the well casing. By this method of operation, after the fine material has been removed there is built up a large filtering system around the well which means a lazy flowage and long life, as the fine sediment lying away from the well will not'be subject to such a high velocity when the water is traveling through, which would otherwise cause the screen to become clogged in a short time.

To enable those skilled in this art to have a. full and complete understanding of the invention and the various structural and functional advantages which accrue from its employment, I have illustrated in the accompanying drawing, forming a part of this specification, a simple appliance for carrying out the preferred method.

In this drawing Fig. 1 is a fragmentary central section through the well-casing and its associated excavating-pump; and

Fig. 2 is a perspective view of a small portion of the apertured, sheet-metal wall of the shell or casing.

Referring to the drawings, it will be perceived that such metal shell or screen 8, which may be of sections longitudinally secured together if desired, is desirably perforated or apertured by providing slits or openings 10 therein by reason of outwardlydeflected or outwardly-pressed strips 9 of the sheet-metal of which the casing is formed, and such shell or screen is provided at its lower end with a cylindrical, sharpedged foot or shoe 11, the casing or shell at its upper end, above the surface of the ground, being fitted or equipped at least temporarily with a Weight 12 of any approved type, shown diagrammatically, to assist in the descent -of the casing.

The pump employed in connection with such apertured screen or casing comprises a cylinder 13 ofabout the same diameter as the internal caliber of the casing, which cylinder at its lower end fits over and is secured to a base-ring 14 having a bottom edge notched or recessed at 15, 15 for the passage inwardly therethrough of Water, earth, gravel, etc, such element 14: within the lower part of the cylindrical shell 13 being equipped with a hinged valve 16 disposed in an inclined relation when closed over the end of member 14 to facilitate its upward opening movement under the suction action to which it is subjected.

Internally, the pump-cylinder accommodates a reciprocatory, perforated or ported iston or (plunger 17 mounted fixedly on the.

ower en of an upright rod or shaft 18 having an eye or loop 19 at its upper end for the attachment of an operating cable or chain, not shown.

A round, flexibldhisk-valve 20, such as of leather or rubber, is positioned over the top, fiat face of the plunger and is adapted to open and close the ports of the latter, depending upon the direction of movement of the parts, all as will be readily understood.

A coiled cushion-spring 21 surrounds the rod or shaft just above the valve, as is clearly indicated At the top end of the pump, the rod or shaft 18 slides through a bearing-block 22 swiveled in the walls of the pump-cylinder, the latter being cut away at one side at 23 for a sidewise discharge of the pumps contents, during which operation the rod or hef 1 y lease of h tar t of. the

bearing-block, occupies a recess or slot 24 cug in the opposite side of the pump-cyl- 1n er.

like, the pump is lowered in the well inside of the casing until the base-ring 14 rests on the earth at the bottom of the Well, in which position it will be surrounded by the foot or shoe 11, and the piston or plunger 17 is permitted to descend, the valve 16 being closed, until it reaches the lower portion of the pump.

-- Then the cable or chain, not shown, en-

the pump and its load are lifted bodily by the further upward movement of the supporting-cable, the valve 16 closes and retains the load in the pump shell or cylinder.

When the screen is to be cleaned, after such loaded pump has been raised or ele- "vated a suflicient distance above the surface of the water in the apertured or perforated screen or casing, it is permitted to fall onto the body of liquid in such casing, creating.

a sudden and sufficient pressure in the liquid to cause it to be forced outwardly through the perforations or holes of the casing or screen and also, at least in some cases, beneath the-lower cutting edge of the shoe or foot 11, so that the screen is in large measure freed from the earth bearing against it, and its descent under the. action of the weight 12 is aided and facilitated, and also effecting the unclogging of the casing slits or apertures by the removal of the dirt therefrom because of the sudden outward flow of water therethrough. This operation is preferably followed by a sudden upward raising of the pump through the screen, which induces a strong inward suction causing the dirt and other fine material pre-= viously dislodged from the scneenopenings on the outer side of the latter to he sucked into the well below the pum By repeating these alternate forcing an sucking operations, the apertures of the screen are very To receive its load of earth, gravel or the facilitating uch Wit drawal taut lit lid

es es by reason of its temporarily washing away the dirt from and around the holes of the cas.

Aer the well has been completel sunk vention and without the sacrifice of any of its substantial benefits and advantages. It

is to be clearly understood that the invention includes and com rehends each of theabove described operations alone, but in its preferred form embraces both operations when performed alternatel I claim: I

1. The method of freeing the apertures of well-casings from clogging material to assist in the casing-shifting o ration, consisting in subjecting the liqui in the wellcasin to a sudden pressure which forces the liquid outwardl through such apertures, and substanti y simu taneously submitting the casing to a force tending to shift it longitudinally in the earth.

2. The method of freeing the aperturesof well-casings from clogging material to assist the casing-shifting operation, consisting in subjecting the liquid in the well-casi to 'a sudden pressure by dropping a weight upon the liquid which forces the latter outwardly. through theeasing-apertures, and substantially "simultaneously submitting the casing toa force tending to shift it longitudinally in the earth.

3. The method of sinking awell-casing consisting in subjecting-the liquid in the well-casing to a sudden suction, and substantially simultaneously subjecting the casing to a downward pressure in the earth.

4. The method of freeing the apertures of well-casings from clogging material, which consists in alternately Sub ectin the liquid within the well-casing to a sud en pressure and a sudden suction.

' WILLIAM H. CATERL, a 8; 

